A maturidade da área de Interação Humano-Computador (IHC) pode ser atestada pela grande quantidade de conjuntos formados por regras, diretrizes e normas (aqui designados como diretivas) que têm sido formulados por dezenas de autores como guias para o estudo, criação e melhoria de interfaces de usuário. No entanto, esses conjuntos apresentam diferenças significativas entre si: muitas dessas diretivas, incluindo algumas já consagradas no universo da IHC, não pertencem ao mesmo nível de abstração nem formam um conjunto homogêneo de enunciados. Essa falta de unidade, aliada à acelerada evolução das tecnologias digitais, tem contribuído para manter essas diretivas (e a própria disciplina de IHC, segundo alguns) em um estado constante de fragmentação e permanente modificação. Mesmo assim, podem ser encontrados princípios — ou leis essenciais, universais e imutáveis — que são subjacentes às diretivas e que podem delas ser extraídos através de uma metodologia adequada. Para contribuir com esse processo, a presente pesquisa apresenta uma revisão dos critérios utilizados para a compilação de conjuntos de diretivas de usabilidade, além de um método de três etapas para a redução progressiva de um número significativo de diretivas a uma lista simples de princípios de usabilidade. Os resultados deste trabalho incluem um modelo metodológico e um conjunto de sete princípios que podem ser utilizados para a pesquisa a e prática da Interação Humano-Computador. / The maturity of the Human-Computer Interaction (HCI) field can be attested by the large number of existing sets of rules, guidelines and standards (called directives herein) that have been formulated by dozens of authors as guidelines for the study, design and improvement of user interfaces. Still, these sets present significant differences among themselves: many of these directives, including some already established in the realm of HCI, do not belong to the same level of abstraction and do not constitute a homogeneous set of statements. This lack of unity, coupled with the rapid evolution of digital technologies, has contributed to maintain these directives (and, according to some, the very discipline of HCI) in a constant state of fragmentation and perpetual change. Even so, it is possible to find among them certain principles — i.e., essential laws that are universal and immutable — which underlie these directives and can be extracted from them using an appropriate methodology. To contribute to this process, this research presents a review of the criteria used to compile these sets of usability directives and a three-step method for the progressive reduction of a significant number of directives to a simple list of usability principles. The results include a methodological framework and seven principles that can be used for the research and practice of Human-Computer Interaction.

A maturidade da área de Interação Humano-Computador (IHC) pode ser atestada pela grande quantidade de conjuntos formados por regras, diretrizes e normas (aqui designados como diretivas) que têm sido formulados por dezenas de autores como guias para o estudo, criação e melhoria de interfaces de usuário. No entanto, esses conjuntos apresentam diferenças significativas entre si: muitas dessas diretivas, incluindo algumas já consagradas no universo da IHC, não pertencem ao mesmo nível de abstração nem formam um conjunto homogêneo de enunciados. Essa falta de unidade, aliada à acelerada evolução das tecnologias digitais, tem contribuído para manter essas diretivas (e a própria disciplina de IHC, segundo alguns) em um estado constante de fragmentação e permanente modificação. Mesmo assim, podem ser encontrados princípios — ou leis essenciais, universais e imutáveis — que são subjacentes às diretivas e que podem delas ser extraídos através de uma metodologia adequada. Para contribuir com esse processo, a presente pesquisa apresenta uma revisão dos critérios utilizados para a compilação de conjuntos de diretivas de usabilidade, além de um método de três etapas para a redução progressiva de um número significativo de diretivas a uma lista simples de princípios de usabilidade. Os resultados deste trabalho incluem um modelo metodológico e um conjunto de sete princípios que podem ser utilizados para a pesquisa a e prática da Interação Humano-Computador. / The maturity of the Human-Computer Interaction (HCI) field can be attested by the large number of existing sets of rules, guidelines and standards (called directives herein) that have been formulated by dozens of authors as guidelines for the study, design and improvement of user interfaces. Still, these sets present significant differences among themselves: many of these directives, including some already established in the realm of HCI, do not belong to the same level of abstraction and do not constitute a homogeneous set of statements. This lack of unity, coupled with the rapid evolution of digital technologies, has contributed to maintain these directives (and, according to some, the very discipline of HCI) in a constant state of fragmentation and perpetual change. Even so, it is possible to find among them certain principles — i.e., essential laws that are universal and immutable — which underlie these directives and can be extracted from them using an appropriate methodology. To contribute to this process, this research presents a review of the criteria used to compile these sets of usability directives and a three-step method for the progressive reduction of a significant number of directives to a simple list of usability principles. The results include a methodological framework and seven principles that can be used for the research and practice of Human-Computer Interaction.

A maturidade da área de Interação Humano-Computador (IHC) pode ser atestada pela grande quantidade de conjuntos formados por regras, diretrizes e normas (aqui designados como diretivas) que têm sido formulados por dezenas de autores como guias para o estudo, criação e melhoria de interfaces de usuário. No entanto, esses conjuntos apresentam diferenças significativas entre si: muitas dessas diretivas, incluindo algumas já consagradas no universo da IHC, não pertencem ao mesmo nível de abstração nem formam um conjunto homogêneo de enunciados. Essa falta de unidade, aliada à acelerada evolução das tecnologias digitais, tem contribuído para manter essas diretivas (e a própria disciplina de IHC, segundo alguns) em um estado constante de fragmentação e permanente modificação. Mesmo assim, podem ser encontrados princípios — ou leis essenciais, universais e imutáveis — que são subjacentes às diretivas e que podem delas ser extraídos através de uma metodologia adequada. Para contribuir com esse processo, a presente pesquisa apresenta uma revisão dos critérios utilizados para a compilação de conjuntos de diretivas de usabilidade, além de um método de três etapas para a redução progressiva de um número significativo de diretivas a uma lista simples de princípios de usabilidade. Os resultados deste trabalho incluem um modelo metodológico e um conjunto de sete princípios que podem ser utilizados para a pesquisa a e prática da Interação Humano-Computador. / The maturity of the Human-Computer Interaction (HCI) field can be attested by the large number of existing sets of rules, guidelines and standards (called directives herein) that have been formulated by dozens of authors as guidelines for the study, design and improvement of user interfaces. Still, these sets present significant differences among themselves: many of these directives, including some already established in the realm of HCI, do not belong to the same level of abstraction and do not constitute a homogeneous set of statements. This lack of unity, coupled with the rapid evolution of digital technologies, has contributed to maintain these directives (and, according to some, the very discipline of HCI) in a constant state of fragmentation and perpetual change. Even so, it is possible to find among them certain principles — i.e., essential laws that are universal and immutable — which underlie these directives and can be extracted from them using an appropriate methodology. To contribute to this process, this research presents a review of the criteria used to compile these sets of usability directives and a three-step method for the progressive reduction of a significant number of directives to a simple list of usability principles. The results include a methodological framework and seven principles that can be used for the research and practice of Human-Computer Interaction.

Les visualisations de données permettent de transmettre de l’information aux utilisateurs. Pour explorer et comprendre les données, les utilisateurs sont amenés à interagir avec ces visualisations.Toutefois, l’interaction avec les visualisations modifie le visuel. Pour éviter des changements brusques et garder l’utilisateur focalisé sur les objets graphiques d’intérêt, des transitions visuelles sont nécessaires pour accompagner les modifications de la visualisation. Ces transitions visuelles peuvent être codées sous la forme d’animations, ou de techniques qui permettent de faire des correspondances, ou des liens avec des données représentées sur plusieurs affichages. Le premier objectif de cette thèse était d’étudier les bénéfices et les propriétés des animations pour l’exploration et la compréhension de grandes quantités de données multidimensionnelles. Nous avons établi en conséquence une taxonomie des transitions animées en visualisation d’information basée sur les tâches des utilisateurs. Cette taxonomie a permis de constater qu’il n’existe pas de contrôle utilisateur sur la direction des objets durant l’animation. Nous avons donc proposé des interactions pour le contrôle de la direction des objets graphiques lors d’une transition animée. D’autre part, nous avons étudié une technique de transition animée mettant en jeu une rotation 3D entre visualisations. Nous avons identifié les avantages qu’elle pouvait apporter et en avons proposé une amélioration.Le second objectif était d’étudier les transitions visuelles dans le domaine du Contrôle du Trafic Aérien. En effet, les contrôleurs utilisent de nombreuses visualisations qui comportent des informations étalées et dupliquées sur plusieurs affichages: l’écran Radar, le tableau de strips, des listes spécifiques d’avions (départ, arrivées) etc. Ainsi dans leur activité, les Contrôleurs Aériens réalisent des transitions visuelles en recherchant et en reliant de l’information à travers les différents affichages. Nous avons étudié comment les animations pouvaient être utilisées dans le domaine du contrôle aérien en implémentant un prototype d’image radar regroupant trois visualisations usuelles pour instrumenter l’activité de supervision du trafic aérien. / Data visualizations allow information to be transmitted to users. In order to explore and understand the data, it is often necessary for users to manipulate the display of this data. When manipulating the visualization, visual transitions are necessary to avoid abrupt changes in this visualization, and to allow the user to focus on the graphical object of interest. These visual transitions can be coded as an animation, or techniques that link the data across several displays. The first aim of this thesis was to examine the benefits and properties of animated transitions used to explore and understand large quantities of multidimensional data. In order to do so, we created a taxonomy of existing animated transitions. This taxonomy allowed us to identify that no animated transition currently exists that allows the user to control the direction of objects during the transition. We therefore proposed an animated transition that allows the user to have this control during the animation. In addition, we studied an animated transition technique that uses 3D rotation to transition between visualizations. We identified the advantages of this technique and propose an improvement to the current design. The second objective was to study the visual transitions used in the Air Traffic Control domain. Air Traffic Controllers use a number of visualizations to view vast information which is duplicated in several places: the Radar screen, the strip board, airplane lists (departures/arrivals) etc. Air traffic controllers perform visual transitions as they search between these different displays of information. We studied the way animations can be used in the Air Traffic Control domain by implementing a radar image prototype which combines three visualizations typically used by Air Traffic Controllers.

South Africans borrow more and save less than other nations (Discovery Bank, 2018). One reason is a lack of financial knowledge. If a mobile application could guide individuals to modify their financial habits slightly by spending less and saving more, they could dramatically improve their financial future. When designing visualisation systems such as a mobile application interface, users' qualitative design feedback and quantitative usability evaluation are both important and complementary. The benefit of usability feedback in software development is undisputed. The importance of qualitative design feedback from users however, seems to be controversial in Science. Gathering users' qualitative design feedback, ahead of usability evaluation, can have a substantial impact on downstream development costs. The researcher used design as a tool for thinking (imagining new possibilities) and communicating (sharing ideas). The purpose was to clarify ways in which a mobile application interface could support users in making better financial decisions and creating better financial futures for themselves and consequently for society. A user centred design (UCD) approach was followed, emphasising design before development, with a strong focus on user involvement in all three phases, namely requirements gathering, design and evaluation. A primary client archetype for mid-career professionals was developed, split into two personas, Alan and Zoe, based on personality and self-rated motivational attributes which were used in an unconventional way to inspire two parallel, diverse designs. In early design stages, before an idea is well formed, producing multiple contrasting designs in parallel and qualitative design feedback from users is beneficial to establishing utility (solving the right problem), tapping into users' domain knowledge, improving the quality of the design and reducing fixation on one idea. Once the concept has been socialised and evolved sufficiently with users' input, converging on one final design and testing usability (solving the problem in the right way) become more important. This research offers two refinements of the UCD process guidelines for the benefit of researchers and practitioners.

La communication affective est au cœur de nos interactions interpersonnelles. Nous communiquons les émotions à travers de multiples canaux non verbaux. Plusieurs travaux de recherche sur l’interaction homme-machine ont exploité ces modalités de communication afin de concevoir des systèmes permettant de reconnaître et d’afficher automatiquement des signaux affectifs. Le toucher est la modalité la moins explorée dans ce domaine de recherche. L’aspect intrusif des interfaces haptiques actuelles est l’un des principaux obstacles à leur utilisation dans la communication affective médiée. En effet, l’utilisateur est physiquement connecté à des systèmes mécaniques pour recevoir la stimulation. Cette configuration altère la transparence de l’interaction médiée et empêche la perception de certaines dimensions affectives comme la valence. L’objectif de cette thèse est de proposer et d’étudier une technique de stimulation tactile sans contact avec des systèmes mécaniques pour médier des signaux d’affects. Sur la base de l’état de l’art des interfaces haptiques, nous avons proposé une stratégie de stimulation tactile basée sur l’utilisation d’un jet d’air mobile. Cette technique permet de fournir une stimulation tactile non-intrusive sur des zones différentes du corps. De plus, ce dispositif tactile permettrait une stimulation efficace de certains mécanorécepteurs qui jouent un rôle important dans les perceptions d’affects positifs. Nous avons conduit une étude expérimentale pour comprendre les relations entre les caractéristiques physiques de la stimulation tactile par jet d’air et la perception affective des utilisateurs. Les résultats mettent en évidence les effets principaux de l'intensité et de la vitesse du mouvement du jet d’air sur l’évaluation subjective mesurée dans l’espace affectif (à savoir, la valence, l'arousal et de la dominance).La communication des émotions est clairement multimodale. Nous utilisons le toucher conjointement avec d’autres modalités afin de communiquer les différents messages affectifs. C’est dans ce sens que nous avons conduit deux études expérimentales pour examiner la combinaison de la stimulation tactile par jet d’air avec les expressions faciales et vocales pour la perception de la valence. Ces expérimentations ont été conduites dans un cadre théorique et expérimental appelé théorie de l’intégration de l’information. Ce cadre permet de modéliser l’intégration de l’information issue de plusieurs sources en employant une algèbre cognitive. Les résultats de nos travaux suggèrent que la stimulation tactile par jet d’air peut être utilisée pour transmettre des signaux affectifs dans le cadre des interactions homme-machine. Les modèles perceptifs d’intégration bimodales peuvent être exploités pour construire des modèles computationnels permettant d’afficher des affects en combinant la stimulation tactile aux expressions faciales ou à la voix. / Affective communication plays a major role in our interpersonal interactions. We communicate emotions through multiple non-verbal channels. Researches on human-computer interaction have exploited these communication channels in order to design systems that automatically recognize and display emotional signals. Touch has receivers less interest then other non-verbal modalities in this area of research. The intrusive aspect of current haptic interfaces is one of the main obstacles to their use in mediated emotional communication. In fact, the user is must physically connected to mechanical systems to receive the stimulation. This configuration affects the transparency of the mediated interaction and limits the perception of certain emotional dimensions as the Valence. The objective of this thesis is to propose and study a technique for tactile stimulation. This technique does not require contact with mechanical systems to transmit affective signals. On the basis of the state of the art of haptic interfaces, we proposed a strategy of tactile stimulation based on the use of a mobile air jet. This technique provides a non-intrusive tactile stimulation on different areas of the body. In addition, this tactile device would allow effective stimulation of some mechanoreceptors that play an important role in perceptions of positive affect. We conducted an experimental study to understand the relationships between the physical characteristics of tactile stimulation by air jet and the emotional perception of the users. The results highlight the main effects of the intensity and the velocity of movement of the air stream on the subjective evaluation measured in space affective (namely, Valence, Arousal and Dominance).The communication of emotions is clearly multi-modal. We use touch jointly with other modalities to communicate different emotional messages. We conducted two experimental studies to examine the combination of air jet tactile stimulation with facial and vocal expressions for perception of the valence. These experiments were conducted in a theoretical and experimental framework called integration of information theory. This framework allows modelling the integration of information from multiple sources using a cognitive algebra. Our work suggests that tactile stimulation by air jet can be used to transmit emotional signals in the context of the human-machine interactions. Perceptual bimodal integration models can be exploited to build computational models to display affects by combining tactile stimulation to facial expressions or the voice.

This work is to investigate the performance of two Kalman Filter Algorithms, namely Linear Kalman Filter and Extended Kalman Filter on control-based human motion prediction in a real-time teleoperation. The Kalman Filter Algorithm has been widely used in research areas of motion tracking and GPS-navigation. However, the potential of human motion prediction by utilizing this algorithm is rarely being mentioned. Combine with the known issue - the delay issue in today’s teleoperation services, the author decided to build a prototype of simple teleoperation model based on the Kalman Filter Algorithm with the aim of eliminated the unsynchronization between the user’s inputs and the visual frames, where all the data were transferred over the network. In the first part of the thesis, two types of Kalman Filter Algorithm are applied on the prototype to predict the movement of the robotic arm based on the user’s motion applied on a Haptic Device. The comparisons in performance among the Kalman Filters have also been focused. In the second part, the thesis focuses on optimizing the motion prediction which based on the results of Kalman filtering by using the smoothing algorithm. The last part of the thesis examines the limitation of the prototype, such as how much the delays are accepted and how fast the movement speed of the Phantom Haptic can be, to still be able to obtain reasonable predations with acceptable error rate.   The results show that the Extended Kalman Filter has achieved more advantages in motion prediction than the Linear Kalman Filter during the experiments. The unsynchronization issue has been effectively improved by applying the Kalman Filter Algorithm on both state and measurement models when the latency is set to below 200 milliseconds. The additional smoothing algorithm further increases the accuracy. More important, it also solves shaking issue on the visual frames on robotic arm which is caused by the wavy property of the Kalman Filter Algorithm. Furthermore, the optimization method effectively synchronizes the timing when robotic arm touches the interactable object in the prediction.   The method which is utilized in this research can be a good reference for the future researches in control-based human motion tracking and prediction. / Detta arbete fokuserar på att undersöka prestandan hos två Kalman Filter Algoritmer, nämligen Linear Kalman Filter och Extended Kalman Filter som används i realtids uppskattningar av kontrollbaserad mänsklig rörelse i teleoperationen. Dessa Kalman Filter Algoritmer har används i stor utsträckning forskningsområden i rörelsespårning och GPS-navigering. Emellertid är potentialen i uppskattning av mänsklig rörelse genom att utnyttja denna algoritm sällan nämnas. Genom att kombinera med det kända problemet – fördröjningsproblem i dagens teleoperation tjänster beslutar författaren att bygga en prototyp av en enkel teleoperation modell vilket är baserad på Kalman Filter algoritmen i syftet att eliminera icke-synkronisering mellan användarens inmatningssignaler och visuella information, där alla data överfördes via nätverket. I den första delen av avhandlingen appliceras både Kalman Filter Algoritmer på prototypen för att uppskatta rörelsen av robotarmen baserat på användarens rörelse som anbringas på en haptik enhet. Jämförelserna i prestandan bland de Kalman Filter Algoritmerna har också fokuserats. I den andra delen fokuserar avhandlingen på att optimera uppskattningar av rörelsen som baserat på resultaten av Kalman-filtrering med hjälp av en utjämningsalgoritm. Den sista delen av avhandlingen undersökes begräsning av prototypen, som till exempel hur mycket fördröjningar accepteras och hur snabbt den haptik enheten kan vara, för att kunna erhålla skäliga uppskattningar med acceptabel felfrekvens.   Resultaten visar att den Extended Kalman Filter har bättre prestandan i rörelse uppskattningarna än den Linear Kalman Filter under experimenten. Det icke-synkroniseringsproblemet har förbättrats genom att tillämpa de Kalman Filter Algoritmerna på både statliga och värderingsmodeller när latensen är inställd på under 200 millisekunder. Den extra utjämningsalgoritmen ökar ytterligare noggrannheten. Denna algoritm löser också det skakande problem hos de visuella bilder på robotarmen som orsakas av den vågiga egenskapen hos Kalman Filter Algoritmen. Dessutom effektivt synkroniserar den optimeringsmetoden tidpunkten när robotarmen berör objekten i uppskattningarna.   Den metod som används i denna forskning kan vara en god referens för framtida undersökningar i kontrollbaserad rörelse- spåning och uppskattning.

The older generation now have plenty of time for daily use of their computers. (1) Nordicom´s Mediabarometer from March 2014 shows that among daily users of the Internet, the age group 65-79 look for more information and digital companionship. On the average day in 2014 they spend 101 minutes on the Net, to be compared with 69 minutes in 2011, an increase of 68 %. Statistics available on the web in 2011 showed the 2009 figures relating to the interest of older adults in using (2) Facebook. Only 4 % of the Swedish users were in the interest group 65 plus, and there was no maximum age. The study intends to find out how potential Facebook users over 65 on sociala media perceive and use Facebook. • How, in wich way, does the older generation use Facebook? • With whom and why? • How use they their social interaction? • Covers Facebook user´s daily needs for information and communication on social media? To have my questions about Facebook answered, I had a questionnare compiled and laid it out on the Web, hoping for replies from potential users. SeniorNet in Sweden is an association of about 50 clubs across the country with 8 500 members. Through contact with SeniorNet in Stockholm area, who mediated my link to their area members, I received answers to my questions. The link to the questionnarie was available for about a month. Of the 90 induviduals who responded, 60 already used Facebook and 30 were not interested in using Facebook. Of the respondents most were woman; 58 woman (64 %) and 32 men (36 %) between 65 and 90. The most frequent use was watching on pictures and status resports of children and grandchildren, and also chatting with old friends and the family. Being able to get quick information about close relatives abroad in the event of natural disasters and not having to worry about them was very important. Being able to follow development of family members with pictures and status reports for those who were living abroad was also important. Availability and having quick answers from Facebook users was the most positive aspect, according to the study. / Den äldre generationen har nu gott om tid att använda datorn dagligen. [1] Nordicoms mediebarometer från mars 2014 visar att åldersgruppen 65-79 år söker mer information och digital gemenskap på nätet dagligen bland dem som använder internet. Användartiden på internet har ökat från 69 minuter 2011, till 101 minuter en genomsnittlig dag 2014, en ökning med 68 %. Statistik som fanns på webben 2011 visade 2009 års siffror, när det gällde äldre vuxnas intresse att använda [2] Facebook. Endast 4 % av Sveriges användare fanns med i intressegruppen 65 plus och det fanns inte någon maximiålder. Avsikten med studien är att få veta hur de som är potentiella användare av Facebook på sociala medier och är 65 plus uppfattar och använder Facebook. • Hur, på vilket vis använder den äldre generationen Facebook? • Med vem, vilka och varför? • Hur använder de sin sociala interaktion? • Täcker Facebook användarnas dagliga behov om information och kommunikation på sociala medier? För att få svar på mina frågor om Facebook lät jag sammanställa en enkät och lade ut den på webben för att få svar från potentiella användare. SeniorNet i Sverige har en sammanslutning av ett 50-tal klubbar i hela landet med 8 500 medlemmar. Genom kontakter med SeniorNet i Stockholms-området, som förmedlade min länk till sina medlemmar i deras områden fick jag svar på mina frågor. Länken med frågeformuläret fanns tillgängligt på webben i ungefär en månad. Av de 90 respondenterna jag fick respons från var 60 redan Facebookanvändare och 30 respondenter hade inte något som helst intresse av att använda Facebook. Det var mest kvinnliga användare 58 kvinnor (64 %) och 32 män (36 %) mellan 65-90 år, som svarade på enkäten. Mest frekvent var att titta på barn och barnbarns bilder och statusrapporter, men även att chatta med gamla vänner och inom familjerna. Att kunna få en snabb information av nära anhöriga utomlands i händelse av naturkatastrofer och att slippa oroa sig för dem var viktigt. Även att kunna följa utvecklingen av anhöriga med bilder och statusrapporter för dem som var bosatta utomlands. Tillgängligheten och att få snabba svar från användare på Facebook var den mest positiva aspekten enligt studien.

The impact of technology is increasing in the automotive industry resulting in user experience to have a significant role in the industry. Previous studies have researched the use of user experience in the automotive industry describing the importance of it. Studies have also described the user experience in connection to in-vehicle functions. Contrariwise, a gap has been identified in relation to the actual use and users’ preferences to these functions. The aim of this study is to analyze the users’ perspective in the automotive industry and how a high level of user experience can be achieved by identifying the preference of the users. This paper aims to identify if functions related to entertainment or functions related to functionality are preferred by the users. It is important to note that the study is not excluding any of the two different type of functions but investigates the preference of the users. Mixed method was used to respond to the research question. Two interviews with experts of the domain of automotive were conducted, where important aspects of the experts’ perspective were covered and was used to develop the survey. In order to achieve a full understanding of the user experience, a survey was sent to identify users’ preferences. The study proved user experience to be important for the organizations in the automotive industry. Moreover, it discovered a discrepancy between the experts’ perspective and the users’ perceptions. Experts expressed customer satisfactions and fulfillment of their demands to be of the primary aim of organizations in the automotive industry. Contrariwise, users expressed that organizations may consider the preference of the users but only to achieve economic and concurrent benefits. Additionally, users expressed a preference to in-vehicle functions related to functionality. More specifically, in-vehicle functions in relation to safety, connectivity and assistance in driving. As a result, this study suggests for organizations in the automotive industry to include the above functions to their vehicles in order to satisfy the demands of their customers and achieve high level of user experience but not exclude the functions related to entertainment.

The theoretical part of the thesis presents the evolution of the fields of human-computer interaction (HCI) and user experience (UX) including hedonic-pragmatic model of user experience. It further presents platforms and ecosystems in general, the evolution of smartphone market and the platforms of Android and iOS, and explains the basic concepts of information and consumer behaviour. A part of the thesis is a qualitative study examining the differences between the preferences towards smartphones of Android and iOS users, and differences in their information behaviour. It was found out that the participants - users of both platforms have mostly pragmatic reasons for their platform preference but describe them differently; that Android users seek more information at the time of smartphone purchase decision and that some iOS users, unlike Android users, started using their platform based on observation of others' good user experience with it.